In the Preliminary Communication entitled “Effect of Moderate-Intensity Exercise Training on Peak Oxygen Consumption in Patients With Hypertrophic Cardiomyopathy: A Randomized Clinical Trial”1 published in the April 4, 2017, issue of JAMA, an author’s middle initial was omitted. In the byline, “Jonathan Herrera” should have appeared as “Jonathan J. Herrera.” This article has been corrected online.